Answer:
The number of proton of magnisium = 12
Answer:So far scientists have not found a way to determine the exact age of the Earth directly from Earth rocks because Earth's oldest rocks have been recycled and destroyed by the process of plate tectonics. If there are any of Earth's primordial rocks left in their original state, they have not yet been found.
Explanation:
486 kPa will be the pressure of gas at 27 degrees.
Explanation:
Data given :
Initial pressure of the gas P1 = 810 kPa
initial temperature of the gas T1 = 227 degrees OR 500.15 K
final pressure of the gas =?
final temperature of the gas = 27 degrees OR 300.15 K
Gay Lussac's law is used to calculate the pressure of the gas at 27 degrees or 300.15 K
= 
P2 = 
Putting the values in the equation:
P2 = 
P2 = 486 KPa
486 Kpa is the pressure of the gas when temperature was reduced to 27 degrees.
Elements in a group or a column have the same number of outer electrons so they have similar chemical properties